Zone Of Cameroon Research Articles

Carbon storage in cashew plantations in Central Africa: case of Cameroon

This study aimed to assess the carbon storage in cashew plantations in the Sudano-Sahelian zone of Cameroon. Quantification of stocks of biomass and carbon dioxide contained in agroforestry systems has become an international priority within the framework of the implementation of REDD + mechanism. Three cashew plantations were selected according to age classes (0–10 years; 10–20 years and over 20 years) in the four subdivisions (Bénoué, Faro, Mayo-Louti and Mayo-Rey). The experimental device installed is a complete random Fisher block with five repetitions. A 100 m × 20 m transect method was undertaken to assess the biomass. Allometric equations were used to assess carbon stock in biomass and laboratory analysis was used to assess soil carbon stock. Carbon stocks varied following the subdivisions and ranged from 69.29 to 96.67; 62.24 to 82.61; 59.00 to 90.64 and 66.14 to 84.03 tC/ha respectively in Bénoué, Faro, Mayo-Louti and Mayo-Rey. Soil carbon stock varied following the subdivisions and ranged from 22.03 to 30.33; 20.12 to 25.43; 19.21 to 25.73 and 21.06 to 24.51 tC/ha respectively in Bénoué, Faro, Mayo-Louti and Mayo-Rey. The highest total carbon stock was recorded in Bénoué subdivision (81.85 ± 13.55 t C/ha). The cashew plantation is actively sequestering carbon showing the potentiality to mitigate global climate change. Finally, these results are also an important economic, ecological and dynamic informative value to serve as a basis for guiding any program of action aimed at the conservation and sustainable management of this species.

Structure and Diversity of Agroforestry Parklands in the Sudano-Sahelian Zone of Cameroon

The general objective of the study is to characterize the woody vegetation of 05 agroforestry parkland in the Sudano-Sahelian zone of Cameroon. A total of 40 floristic surveys of 200  20 m were carried out. A total of 33 species in 20 families and 31 genera were recorded. The dendrometric survey method enabled us to characterize the vegetation of the agroforestry parks. The dendrometric parameters and indices calculated according to the agroforestry parks vary from one park to another. Thus, density varies from 108±2.98-223±8.01 individuals/ha, recovery from 6.11±0.21-10.12±0.31%, basal area from 6.54±1.12 to 10.05±1.87 m²/ha, biovolume from 20.09±2.22-38.54±3.76 m3/ha, total height from 2.11±0.01-5.06±0.04 m, natural regeneration rate from 2.11±0.52-7.40±1.09%. The Shannon index varies from 1.36±0.20-2±0.29 bits, Pielou index from 0.14±0.07-0.35±0.18 and Simpson index from 0.82±0.02-0.97±0.03. The species with the highest SIV and SIR are Combretum glutinosum, Combretum adenogonium, Sclerocarya birrea, Prosopis africana, Entada africana, Anacardium occidentale, Burkea africana, Maytenus senegalensis, Ficus glumosa. The Mimosaceae, Caesalpiniaceae, Combretaceae show a high representativeness in relation to their family importance value. The diameter structure showed a predominance of young individuals and the height structure showed a predominance of individuals of class [4-6 m]. These results can be used as a reference in monitoring the vegetation dynamics of agroforestry parks subject to recurrent droughts and anthropogenic pressures. This study provides a better understanding of the vegetation in agroforestry parks in order to better manage these plant resources.

In vitro Protein Digestibility and Iron Bioavailability According to Agro-Ecological Zone and Stage of Maturity of Moringa oleifera Lam Leaves

This study aims to determine the influence of agro-ecological zone and stage of maturity on in vitro protein digestibility (IVPD) and iron bioavailability from Moringa oleifera.leaves. The young and mature leaves were collected from three farms in each agro-ecological zone in Cameroon and processed in powders. Nutrient contents (proteins, total and free iron), bioactive compounds (total fiber, total polyphenols, phytates), IVPD, and iron bioavailability were determined. The stage of maturity affects significantly the variations of total iron contents (90.10%) while the agro-ecological zone affects significantly the variations of total polyphenol (48.28%), total fiber (80.97%), and phytates (46.48%) contents. Total protein contents were affected by the interaction of both (35.88%). Mature leaves have higher total iron, bioactive compounds contents in the mean compared to young leaves, and whatever the agro-ecological zone and stage of maturity of leaves, the IVPD is near casein, and bioavailability of iron is low. The young leaves have higher IVPDs and lower bioavailability of iron while mature leaves have lower IVPDs and higher bioavailability of iron. To alleviate protein malnutrition and iron deficiency through the utilization of M. oleifera leaves, it’s necessary to consider the effects of stage of maturity and agro-ecological zone on bioactive compounds contents and their anti-nutritional properties.

Habitats of antlions larvae (Neuroptera: Myrmeleontidae) in the Sudano-Guinean and Sudano-Sahelian zones of Cameroon

Antlions (Insecta: Neuroptera) are flying insect associated with sunny weather at adult stage. During larval stage, xerophilous insects they are familiar to arid soils with critical temperature, hygrometry and luminosity. These 3 climatic parameters are used to discriminate among larval habitats of antlions in the Soudano Guinean and Soudano Sahelian Savannah of Cameroon. Investigations made during 3 years from 2015 to 2018,consisted in survey of larvae’s funnels. At the level of each active pit-traps, the 3 parameters were recorded during the whole dry season. Analysis of data computerised pointed out that larvae of Cueta bourborni Navas 1935, and those of Cueta sp, are frequent within sites that are warm (40.57±0.64°C to 52.14±4.08°C); dry (10.91±0.82-16.81±2.74%rh) and lighted (94380.2 ±16109.4 lux) habitats. On the other hand, larvae of Myrmeleonquinquemaculatus Hagen 1853 are associated with sites that are: humid (75.46±4.50% RH), cloudy (448.232±300. 491 lux) with tendency to moist (22.11±0.88°C to 28.10 ±2.14°C). Presence of C. bourbonni sometimes in the moisty Soudano Guinean zone could only indicate episode of warming.
 Keywords. Antlions habitats, global warming, temperature, luminosity, Hygrometry

Socio-Economic Household Surveys on the Application of Basic Preventive Measures Dictated by the WHO to Stop the Spread of COVID-19 in the Northern Zone of Cameroon

Currently, the emergence of a new human coronavirus, COVID-19, is of concern to all humanity. In order to understand the effect of this disease on the behavior of populations, we conducted surveys of 900 households in 300 households per Region (Adamawa, North, and Far North) in Northern of Cameroon. The surveys focused on compliance with the basic preventive measures dictated by the WHO, the means developed by households to block the way to this COVID-19, and the activities that occupy them during the period of confinement.

Mapping lymphatic filariasis in Loa loa endemic health districts na\xefve for ivermectin mass administration and situated in the forested zone of Cameroon

BackgroundThe control of lymphatic filariasis (LF) caused by Wuchereria bancrofti in the Central African Region has been hampered by the presence of Loa loa due to severe adverse events that arise in the treatment with ivermectin. The immunochromatographic test (ICT) cards used for mapping LF demonstrated cross-reactivity with L. loa and posed the problem of delineating the LF map. To verify LF endemicity in forest areas of Cameroon where mass drug administration (MDA) has not been ongoing, we used the recently developed strategy that combined serology, microscopy and molecular techniques.MethodsThis study was carried out in 124 communities in 31 health districts (HDs) where L. loa is present. At least 125 persons per site were screened. Diurnal blood samples were investigated for circulating filarial antigen (CFA) by FTS and for L. loa microfilariae (mf) using TBF. FTS positive individuals were further subjected to night blood collection for detecting W. bancrofti. qPCR was used to detect DNA of the parasites.ResultsOverall, 14,446 individuals took part in this study, 233 participants tested positive with FTS in 29 HDs, with positivity rates ranging from 0.0 to 8.2%. No W. bancrofti mf was found in the night blood of any individuals but L. loa mf were found in both day and night blood of participants who were FTS positive. Also, qPCR revealed that no W. bancrofti but L.loa DNA was found with dry bloodspot. Positive FTS results were strongly associated with high L. loa mf load. Similarly, a strong positive association was observed between FTS positivity and L loa prevalence.ConclusionsUsing a combination of parasitological and molecular tools, we were unable to find evidence of W. bancrofti presence in the 31 HDs, but L. loa instead. Therefore, LF is not endemic and LF MDA is not required in these districts.

In vitro biological activities of aqueous extracts of Tetrapleura tetraptera (Schumach. & Thonn.) taub. and Aframomum citratum (C. Pereira) K.Schum from three Agroecologic Zones in Cameroon

Objective: To investigate some phytochemical constituents and biological activities of twelve samples of Tetrapleura tetraptera (Schumach & Thonn.) taub. and nine samples of Aframomum citratum (C. Pereira) K. Schum fruits collected in the bimodal forest zone (ZONE V), the unimodal forest zone (ZONE IV) and the highlands zone (ZONE III) in Cameroon. Methods: Fresh fruits extracts were obtained by aqueous infusion (100 °C during 15 min) and evaluated by spectrophotometric methods for total polyphenol (TPP), total flavonoids (TFLV) contents and antioxidant (DPPH, total antioxidant capacity by the phosphomolybdenum method, iron reducing power or ferric reducing antioxidant power and inhibition of beta carotene discoloration assays) and anti-inflammatory (inhibitions of protein denaturation and 5-LOX represented by INH.PROT and INH.5- LOX respectively) properties. Principal component analysis was performed. Results: For both species, fruits from ZONE V have the highest TPP, TFLV levels and biological activities. TPP and TFLV content of Aframomum citratum and Tetrapleura tetraptera fruits are positively and significantly (P Conclusions: The fruits exhibit variabilities and those from ZONE V for both species are economically and healthcare challenging for herbalists, pharmaceutical firms, scientists and consumers. Indeed, most important extraction yield of bioactive compounds correlated with significant biological activities and the use of less material compared with an implementation in other Agro-ecologic Zones with the same results are noted.

Soil Organic Carbon Stock under Different Age Ranges of Cashew Agroecosystems in the Sudano-Sahelian Zone of Cameroon

The aim of this study was to quantify the current soil organic carbon stock under different age ranges of cashew agroecosystems in the Sudano-Sahelian zone of Cameroon in the context of greenhouse gas emissions and land degradation. It is so crucial for combating climate change and improving ecological restoration. Random field sampling was carried out on 0-10, 10-20 and 20-30 cm depths were collected in three age groups (0-10; 10-20; over 20 years old) of Cashew agroecosystems. Soil bulk density, Soil reaction (pH), moisture content, total nitrogen, C/N ratio, particle size distribution and soil organic carbon were determined using standard laboratory procedures and calculations. The results of the study did not reveal a significant difference in soil organic carbon stock across the different age groups of the cashew agroecosystems (P>0.05). The highest values of soil organic carbon stocks were observed in the 0-10 cm depth. Soils under plots with over 20 cashew agroecosystems in Benoue subdivisions recorded higher SOCS values (36.30±2.92 tC/ha). Similarly, the SOCS decreased with soil depth in all three age groups of Cashew agroecosystems. The mean SOC concentrations (%) ranged from 0.20±0.02-0.41±0.10%. Soil organic carbon stock ranged from 16.45±0.73-37.04±2.32 tC/ha depending on depth between the three age ranges of Cashew agroecosystems studied in the four subdivisions. The Cashew agroecosystems soils with high C stock are those with sandy loamy texture (25.79±2.29 tC/ha). Results showed a positive and significant (P 0.05) with % Sand, % Silt, % Clay, % Silt + Clay. The results show the potential contribution of Cashew agroecosystems to improve soil organic carbon sequestration and environmental protection. This information will be necessary for developing appropriate technological and political solutions to increase agricultural sustainability and combat environmental degradation in the Sudano-Sahelian zone of Cameroon.

Vegetation Structure, Root Biomass Distribution and Soil Carbon Stock of Savannah Agrosystems in Sudano-Sahelian Zone of Cameroon

Cotinus coggygria Scop. is widely used in ethnopharmacology such as antiseptic, anti-inflammatory, antimicrobial, hepatoprotective, as well as for countering diarrhea, gastric and duodenal ulcers. Total phenols, flavonoids and tannins were determined as the main group of biologically active compounds. Tannins, however, have proven mutagenic in different studies.

Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in Cameroon: Case study on its distribution, damage, pesticide use, genetic differentiation and host plants.

Maize farmers in sub-Saharan Africa recently experienced unusual damage in their farms, attributed to the fall armyworm (FAW) Spodoptera frugiperda (J. E. Smith). This pest was first recorded in Africa in 2016, but detailed information on its distribution and damage and farmer’s response in invaded areas are largely lacking. In this study, we determined FAW distribution, genetic diversity, host plants, crop damage, and farmers’ responses. S. frugiperda was recorded in the 10 regions of Cameroon. Average percentage of infested plants and damage severity (on a scale of 1 to 5) were lowest—20.7 ± 7.4% and 2.1 ± 0.1 respectively—in the Sahelian regions and greatest—69.0 ± 4.3% and 3.1 ± 0.1 respectively—in the Western Highlands. Altitude did not influence FAW incidence and severity and its larvae infrequently co-occurred with maize stemborers on the same plants, suggesting possible direct and/or indirect competition between the two groups of maize pests. In response to this new threat to maize production, farmers have opted for the application of synthetic pesticides. Although our experiments were not designed to determine pesticide efficacy, as parameters such as time since application were not considered, our observations suggest lack of a drastic effect on S. frugiperda infestations on maize. There were two haplotypes of FAW co-occurring in Cameroon corresponding to the rice and corn strains and separated by 1.7% sequence divergence, which does not support the existence of cryptic species. S. frugiperda larvae were also recorded on Sorghum bicolor (L.) Moench (10.6%), Solanum tuberosum L. (2.8%), Ipomoea batatas (L.) Lam. (1.9%), Saccharum officinarum L (0.8%), Phaseolus vulgaris L. (0.4%) and Gossypium hirsutum L. (1.9%). This study show that two strains are present in all agroecological zones in Cameroon, and probably in neighboring countries of central Africa sharing the same agroecologies. Management options should therefore consider the use of specific natural enemies and an informed decision of intervention based on strain capture and damage threshold, to avoid pesticide resistance that may arise from inadequate use of chemicals. Further studies should also be undertaken to assess the response of the two S. frugiperda strains to biopesticides and botanical insecticides.

Demographical, hematological and serological risk factors for Plasmodium falciparum gametocyte carriage in a high stable transmission zone in Cameroon.

Presence of mature gametocyte forms of malaria parasites in peripheral blood is a key requirement for malaria transmission. Yet, studies conducted in most malaria transmission zones report the absence of gametocyte in the majority of patients. We therefore sought to determine the risk factors of both all-stage and mature gametocyte carriage in an area with high stable transmission of Plasmodium falciparum in Cameroon. Gametocyte positivity was determined using three complementary methods: thick blood smear microscopy, RT-PCR and RT-LAMP, whereas exposure to the infection was assessed by enzyme-linked immunosorbent assay. Of 361 malaria endemic residents randomly included in the study (mean age: 28±23 years, age range: 2–100 years, male/female sex ratio: 1.1), 87.8% were diagnosed with P. falciparum infection, of whom 45.7% presented with fever (axillary body temperature ≥37.5°C). Mature gametocyte positivity was 1.9% by thick blood smear microscopy and 8.9% by RT-PCR targeting the mature gametocyte transcript, Pfs25. The gametocyte positivity rate was 24.1% and 36.3% by RT-PCR or RT-LAMP, respectively, when targeting the sexual stage marker, Pfs16. Multivariate analyses revealed anemia as a common independent risk factor for both mature and all-stage gametocyte carriage, whereas fever and low anti-gametocyte antibody levels were independently associated with all-stage gametocyte carriage only. Taken together, the data suggest important differences in risk factors of gametocyte carriage depending on stage analyzed, with anemia, fever and low antiplasmodial plasma antibody levels representing the major contributing risk factors.

Zircon chemistry and new laser ablation U–Pb ages for uraniferous granitoids in SW Cameroon

The Ekomedion two-mica granite, southwestern Cameroon, has potential for uranium and molybdenum mineralization. Here, we present LA-ICP-MS U–Pb ages, Lu–Hf isotope characteristics, trace element concentrations and Ti-geothermometry of zircon from this granite hosting U–Mo mineralization in pegmatitic pods. The majority of zircon are CL-dark though some CL-bright cores were also identified. U–Pb zircon age data range from 121 ± 3 to 743 ± 11 Ma with only 5 of 34 ages being near concordant. The concordant mean age of 603 ± 12 Ma is similar to ages of granitic intrusions along the Central African Shear Zone in Cameroon. Apparent ages with mean of 261 ± 6 Ma reveal open system behavior with respect to Pb and/or U. Zircon eHfi values range from − 20.3 to − 0.3. This implies that U–Mo was remobilized during partial melting of the surrounding gneiss. Zircon Th/U > 0.1 as well as an increasing Hf with decreasing Th/U indicates that fractional crystallization was the main factor that controlled U–Mo mineralization in pegmatitic pods. Y and Y/Ho ratios cluster from 29 to 33 close to the chondritic ratio of 28 and indicate fractionation of Y and Ho with low F contents during the earliest stages of crystallization. Late stage accumulation of F-rich magmatic-hydrothermal fluids impacted U–Mo mineralization as a ligand. Zircon contains a prominent negative Eu anomaly pointing to a fractionating system rich in plagioclase. Calculated Ti-in-zircon temperatures span 672 °C to 1232 °C with the temperatures at the high end reflecting interference from mineral inclusions in the zircon grains while the lower temperature values are linked to crystallization.

Comparative analysis of IgG and IgG subclasses against Plasmodium falciparum MSP-119 in children from five contrasting bioecological zones of Cameroon

BackgroundStudies reporting the natural immune responses against malaria in children from different geographical settings in endemic areas are not readily available. This study was aimed at comparing the immune responses against Plasmodium falciparum MSP-119 antigen in children from five contrasting bioecological zones in Cameroon.MethodsIn a cross-sectional survey, children between 2 and 15 years, were enrolled from five ecological strata including the south Cameroonian equatorial forest, sudano-sahelian, high inland plateau, high western plateau, and the coastal strata. The children were screened for clinical malaria (defined by malaria parasitaemia ≥ 5000 parasites/µl plus axillary temperature ≥ 37.5 °C). Their antibody responses were measured against P. falciparum MSP-119 antigen using standard ELISA technique.ResultsIn all, 415 children comprising 217 (52.3%) males participated. Total IgG and IgG1–IgG4 titres were observed to increase with age in all the strata except in the sudano-sahelian and high inland plateau strata. Total IgG and IgG1–IgG4 titres were significantly higher in the coastal strata and lowest in the high inland plateau (for IgG1 and IgG2) and sudano-sahelian strata (for IgG3 and IgG4). Titres of the cytophilic antibodies (IgG1 and IgG3) were significantly higher than the non-cytophilic antibodies (IgG2 and IgG4) in all the strata except in the sudano-sahelian and high inland plateau strata. Total IgG and IgG subclass titres were significantly higher in children positive for clinical malaria compared to negative children in all study sites except in the high western plateau and coastal (for IgG1 and IgG3), and the sudano-sahelian strata (for all antibodies). Furthermore, a significant positive correlation was observed between parasite density and IgG2 or IgG4 titres in all study sites except in the south Cameroonian equatorial forest and sudano-sahelian strata.ConclusionsThis study showed that antibody responses against MSP-119 vary considerably in children from the different bioecological strata in Cameroon and could be linked to the differential exposure to malaria in the different strata. Furthermore, the rate of antibody acquisition was not observed to increase in an age-dependent manner in low transmission settings.

Phytoecological valorization attributes of Mozogo-Gokoro National Park (Cameroon).

Natural and anthropogenic pressures are major concerns about the stability of vegetation in protected areas of the Sudano-Sahelian regions. This study aims to describe the woody flora of Mozogo-Gokoro National Park, submitted to these geographical area constraints in the Far North of Cameroon. Global inventory of this flora is carried out, through three collection units representing strata in vegetation that are previously identified by photo-interpretation, with analyses focusing on compositional diversity parameters. Results show a very rich woody flora (110 woody plant species, for 46 genera and 30 families), having a quasi-typical Sudano-Sahelian physiognomy. Vegetation is mainly a shrubby dry forest, dominated by species such as Senegalia ataxacantha, Anogeissus leiocarpa, Tamarindus indica, Psorospermum senegalense, Clerodendrum capitatum, Celtis toka, and the botanical families of Fabaceae and Combretaceae. The diversity indices, the woody density, and the basal area are high (4.32 bits for the Shannon-Weaver index, 2694.16 stems/ha and 43.89m2/ha). Despite the dominance of Sahelian individuals, the importance of Sudanian and Guinean species (more than 22.68% of species) brings vegetation closer to those of much humid areas. In wooded savanna collection unit, several values of the evaluated parameters are lower in comparison with those obtained in the two others. However, these fluctuations related to the degradation of vegetation are insignificant, indicating a preserved resilience. The Mozogo-Gokoro National Park stands as a model of plant conservation in the Sudano-Sahelian zone in Cameroon, hence the major interest to be granted for its conservation and sustainable management.

Comparing Freshwater Benthic Macroinvertebrate Communities in Forest and Urban Streams of the Coastal Ecological Region of Cameroon

In this study conducted in the coastal zone of Cameroon, biological indices and functional feeding groups of benthic macroinvertebrates were used to assess the health status of two urban streams. For a better diagnosis, two streams located in coastal forest zone were used as a reference. Benthic macroinvertebrates were sampled monthly over a 3-month period (from May to July 2017) in six urban stations and six forest stations. Measurements of the physicochemical variables were done simultaneously. Physicochemical analysis revealed that urban streams are strongly polluted with high content of decaying organic matters, while forest streams are slightly polluted as indicated by the Principal Component Analysis. Concerning benthic macroinvertebrates, urban streams are poorly diversified with the proliferation of taxa tolerant to water pollution and belonging to the functional feeding groups of collectors-gatherers. Inversely, forest streams are more diversified and dominated by sensitive taxa, most belonging to the functional feeding groups of predators and shredders. These marked differences between biological indices and feeding mode of benthic macroinvertebrates in forest and urban rivers confirm the reliability of benthic macroinvertebrates as good indicators of freshwater ecosystem in the coastal zone of Cameroon.

Organisations paysannes et développement socio économique dans la zone forestière du Cameroun méridional, 1992 à 2015

O objetivo deste artigo é mostrar o contributo das organizações camponesas para a promoção do mundo rural na zona florestal do sul dos Camarões desde 1992, ano em que um decreto do presidente da República autorizou a criação de grupos de agricultores, até 2015. Com base em fontes arquivísticas, fontes orais e uma bibliografia seletiva, este artigo trata do surgimento das organizações de agricultores nas regiões do Camarões Central e do Sul e aborda as suas atividades e o seu impacto ao desenvolvimento rural.Nossas análises mostram que a retirada do Estado do setor produtivo na década de 1990 e o quadro legislativo implementado pelas autoridades públicas favoreceram a criação de várias organizações no mundo rural na zona florestal. Essas associações camponesas contribuem para o desenvolvimento rural através do desenvolvimento da agricultura, do processamento e da comercialização de produtos e de fundos de poupança. O dinheiro dessas atividades permite que os membros dessas associações camponesas melhorem suas condições de vida.

Susceptibility Zonation of the Soils of Mayo-Danay in East Part of the Sudano-Sahelian Cameroon, Central Africa

The study of soil resources of Mayo-Danay, located in the tropical zone of Cameroon, shows a diversity of soils characterized by specific properties. Indeed, this study area is generally a plain landscape whose average relative altitude (300 m). However, it indicates a vegetation of savanna type, very dominant. Hydrologically, Logone River, Maga Lake and tributary streams of the Mandara Mountains regularly flood the study area. The sharing of these parameters leads to soil’s genesis, which have a sandy texture for floodplain soils and a very dominant clay texture for lacustrine soils. Otherwise, the geochemistry of these soils shows SiO2 contents globally 70% in the different soils studied; Al2O3 contents are less than 10% in lacustrine soils and less than 5% in floodplain soils; while the major elements data of soils such as Fe2O3, CaO and MgO indicate relatively low contents (≤2%) on soils studied. In addition, the mineralogy index of alteration expresses a moderate alteration of these soils. Thus, the distribution of these major elements of soil reveals its susceptibility to zonation, which is a consequence of intrinsic and extrinsic parameters to formation and differentiation of soils of the study area.

Impact of Management Practices in Industries in the Industrial – Free – Trade Zones in Douala, Littoral Region of Cameroon: “Challenges and Prospects”

In Cameroon of late, there is growing consciencious that the deleterious impacts of industrial activities on safety health and environmental quality has motivated government and industries to adopt environmental management practices such as the EMSs and EMA, that is, Environmental Management Systems, and Environmental Management Accounting respectively at the least. This paper however, examines the implementation of EMSs and EMA amongst others in industries in the Industrial –Free – Trade Zones of the South West and Littoral Regions of Cameroon that interact with its environment which has been affected by the effluents emanating from industrial activities.This paper also presents an overview of various initiatives like policies that have been crafted by the government of Cameroon to address the problems of industrial activity such as pollution etc. It also seeks to prescrible recommendations which could be used to save the regions, from industrial pollution. After the participation of Cameroon in the Earth’s Summit in Rio de Janerio, Brazil (1992), and ever since the publication of the Brunditland Commission’s Landmark Report ‘‘Our Common Future’’, in (1987), the government has taken significant steps to overhaul its institutional framework vis – à – vis the regulation of industrial pollution.Through a questionnaire based survey carried but from January to July 2016 with the sampled industries in the Industrial – Free – Trade – Zones of the South West and Littoral Regions of Cameroon, data was collected. This paper also aims at addressing motivational factors, implementation hurdles as well as benefits accrued by these industries as a result of adapting environmental management systems in their management practices generally. Studies also support that many benefits arise as a result of EMSs and EMA enforcement, but the paradox is the plethora of hurdles that still persist in industries. Against this background, this paper concludes by prescribing recommendations that seek to promote management practices such as EMSs and EMA in industries in Industrial – Free – Trade – Zones in Cameroon.

Agro-ecological distribution of the phenotypic diversity of aerial yam (Dioscorea bulbifera L.) in Cameroon using multivariate analysis: prospect for germplasm conservation and improvement

Abstract Aerial yam (Dioscorea bulbifera L.) is a crop of great economic importance and an excellent candidate for improving food security in developing countries. Understanding the genetic variability of any crop species is a decisive step for its improvement and requires characterization and evaluation of available germplasm. The objectives of this study were to determine the extent of genetic variability, estimate the association between agromorphological traits and clustering among 57 genotypes of aerial yam from three distinct agro-ecological zones in Cameroon using multivariate analysis. Thirty nine characters (23 qualitative and 16 quantitative) were used for the study. Significant differences in genetic diversity indices were found. Accessions from the bimodal humid forest zone (Na = 2.08, He = 0.27) showed significantly lower diversity compared to both western highland (Na = 2.30, He = 0.34) and humid monomodal forest zones (Na = 2.57, He = 0.32). Means values of most quantitative traits also showed significant differences between agro-ecological zones. Batingla-3 and Bawouwoua-1 had important bulbil yield, reaching 3500 g / plant. Significant associations were found between many traits. The use of the Unweighted Pair Group Method with Arithmetic Mean allowed the distribution of the 57 genotypes into six distinct clusters with the clustering pattern not showing any parallelism with location sites or agro-ecological zones. Mahalanobis D2 statistics revealed the highest inter-cluster distance between cluster II and VI. Accessions of these clusters are potential parents for future breeding programs. This study showed that aerial yam from Cameroon has an enormous wealth of traits variation, indicating huge potential for its genetic improvement through selection and hybridization.

Technical Efficiency among Smallholder Rice Farmers: A Comparative Analysis of Three Agro‐ecological Zones in Cameroon

AbstractRice production in Cameroon is characterized by smallholder type of production, disease‐plagued farms, huge inefficiency, and largely depends on agro‐ecological conditions. So, the country imports most of its domestic consumption needs of rice. Using survey data from 1,141 Cameroonian smallholder rice farmers, their scores of technical efficiency, determinants and the extent of their variability across three agro‐ecological zones are analyzed. The results suggest significant room for improvement in the farmers’ technical efficiency which varies largely across and within agro‐ecological zones. Correlates of technical efficiency differentials among the farmers differ across agro‐ecological zones, ranging from the age and experience of farmer and land ownership in the Sahel, age of farmer, land ownership and distance village‐farm in the western highland, to agricultural training in the bimodal humid rain forest zone.